Salinity gradient power generation apparatus and method, and water-electricity co-generation apparatus thereof

Abstract

The present application relates to the technical field of comprehensive utilization of waste heat, and discloses a salinity gradient power generation apparatus and method, and a water-electricity co-generation apparatus thereof. In the salinity gradient power generation apparatus and method provided in the present application, an anode and a cathode respectively undergo hydrogen oxidation and reduction reactions, the anode consumes hydrogen, the cathode generates hydrogen, and the hydrogen circulates between the cathode and the anode by means of pipes without net consumption, thereby efficiently utilizing salinity gradient energy, achieving an environmentally friendly process, and producing no carbon emissions; compared with redox reaction systems using Fe2+ / Fe3+ or ferricyanide / ferrocyanide, the system is free from the limitation of concentration polarization; compared with redox systems based on water electrolysis, lower overpotential and higher efficiency are achieved; and a small amount of H2 is used, with no safety risk and no net consumption throughout the system. The water-electricity co-generation apparatus based on the salinity gradient power generation apparatus of the present application can make full use of waste heat to produce fresh water and generate electricity simultaneously, achieving high efficiency and pollution-free operation.

Description

A device and method for salinity gradient power generation and a water-electricity cogeneration device thereof TECHNICAL FIELD

[0001] The present application relates to a device and method for salinity gradient power generation and a water-electricity cogeneration device thereof, and belongs to the technical field of comprehensive utilization of waste heat. BACKGROUND

[0002] Waste heat is the energy in the form of heat discharged into the air during industrial production. Although this part of heat cannot be utilized by existing industrial systems, it can still be recovered for effective energy through other means due to its higher temperature than the ambient temperature. There are various ways to utilize waste heat, and desalination of seawater through waste heat is a relatively mature technology, mainly including low-temperature multi-effect (MED), multi-stage flash distillation (MSF), and pressure vapor distillation desalination processes.

[0003] Seawater desalination, also known as seawater desalting, removes excess minerals and salts from water and divides the water source into low-salinity freshwater and high-salinity brine. The salinity of brine is about twice that of seawater, and direct discharge of brine into the sea or dilution before discharge will affect the marine ecological environment. To solve the problem of marine environmental pollution caused by the discharge of brine into the sea and make full use of seawater resources, integrated technologies for comprehensive utilization of concentrated seawater have been developed in recent years, including seawater salt making, seawater potassium extraction, seawater bromine extraction, seawater magnesium extraction, etc.

[0004] In fact, the chemical potential difference between brine and river water is equivalent to a water level difference of about 300-400m, which contains a huge amount of salinity gradient energy that can be directly converted into electrical energy. In this way, while producing freshwater through waste heat, salinity gradient energy can be used to generate electricity, achieving two goals at once.

[0005] The current technology for direct salinity gradient power generation is reverse electrodialysis (RED). This technology places ion-selective membranes between salt solutions of different concentrations, and uses the concentration difference between different ions to make them migrate directionally between the ion exchange membranes, thereby directly converting chemical potential energy into electrical energy. The main device is a RED module composed of an anode, alternating cation and anion exchange membranes, and a cathode. The alternating cation and anion exchange membranes are separated by a separator to form independent concentrated water chambers and freshwater chambers. When concentrated and dilute salt solutions enter the module and flow in their respective chambers, the cations and anions in the concentrated salt solution migrate into the freshwater chamber through the cation and anion exchange membranes, respectively, driven by the concentration difference, thereby forming an internal current. The internal current can be converted into an external circuit current through the oxidation-reduction reaction of the anode and cathode. The current electrode reaction is mainly the oxidation-reduction reaction of Fe 2+ / Fe 3+ or ferricyanide / ferrocyanide, or an irreversible water electrolysis reaction. Irreversible reactions consume energy and reduce efficiency. Even if Fe 2+ / Fe 3+or ferricyanide / ferrocyanide, large stack voltage and large current, greater than 10V, when using tens of hundreds of repeat units, also promote water electrolysis reactions, which is mainly due to the Fe 2+ / Fe 3+ Active material mass transfer is limited, and continuous redox reaction cannot be maintained.

[0006] SUMMARY

[0007] To solve the foregoing problems existing in the existing salt difference power generation and make full use of the brine produced by waste heat desalination, the application provides a salt difference power generation device and method and a water-electricity cogeneration device thereof, which utilizes the salt difference between the brine produced by seawater desalination and fresh water / sea water to directly generate power while desalinating seawater by using waste heat.

[0008] The application adopts the following technical solutions:

[0009] A salt difference power generation device comprises oppositely arranged anode 101 and cathode 401.

[0010] The anode 101 is provided with an anode side cation exchange membrane 102 on the side close to the cathode 401, the anode side cation exchange membrane 102 is provided with an anode side electrode liquid chamber 103 on the side away from the anode 101, and the anode 101 is provided with an anode chamber 104 on the side away from the cathode 401.

[0011] The cathode 401 is provided with a cathode side cation exchange membrane 402 on the side close to the anode 101, the cathode side cation exchange membrane 402 is provided with a cathode side electrode liquid chamber 403 on the side away from the cathode 401, and the cathode 401 is provided with a cathode chamber 404 on the side away from the anode 101.

[0012] The anode side electrode liquid chamber 103 and the cathode side electrode liquid chamber 403 are connected by external pipelines to form a loop for circulating electrolyte.

[0013] At least one brine chamber 301 and at least one fresh water chamber 302 are arranged between the anode side electrode liquid chamber 103 and the cathode side electrode liquid chamber 403, and the brine chamber 301 and the fresh water chamber 302 are separated by a partition plate.

[0014] The partition plate is provided with a cation exchange membrane 201 or an anion exchange membrane 202, the partition plate is insulated, and the specific position of the cation exchange membrane 201 or the anion exchange membrane 202 on the partition plate is not strictly limited, for example, it can be on one side, both sides or in the middle of the partition plate.

[0015] The cation exchange membrane 201 is arranged on the side of the brine chamber 301 close to the anode side electrode liquid chamber 103 and the side of the fresh water chamber 302 away from the anode side electrode liquid chamber 103.

[0016] The brine chamber 301 is adjacent to one side of the cathode-side electrode solution chamber 403, and the fresh water chamber 302 is away from one side of the cathode-side electrode solution chamber 403, and an anion exchange membrane 202 is arranged therebetween.

[0017] Optionally, a plurality of brine chambers 301 and fresh water chambers 302 are arranged alternately between the anode-side electrode solution chamber 103 and the cathode-side electrode solution chamber 403.

[0018] Optionally, the anode 101 and the cathode 401 are both gas diffusion electrodes.

[0019] The gas diffusion electrode is composed of a support layer, a microporous layer, and a catalytic layer.

[0020] The support layer is selected from at least one of carbon paper, carbon cloth, carbon felt, metal mesh, and foamed metal.

[0021] The microporous layer is formed by curing a mixture of carbon powder and a binder I.

[0022] The binder I is selected from at least one of PTFE, PVDF, FEP, and PFA.

[0023] The catalytic layer is formed by curing a mixture of an electrocatalyst and a binder II.

[0024] The binder II is selected from at least one of PTFE, PVDF, FEP, PFA, and cation exchange resin.

[0025] The active component of the electrocatalyst is selected from at least one of platinum, palladium, ruthenium, nickel, chromium, cobalt, copper, tungsten, iron, cerium, molybdenum, and lead.

[0026] Optionally, the electrocatalyst is a carbon-supported catalyst that supports the active component.

[0027] Optionally, the anode 101 and the cathode 401 are both provided with a current collector on the outer side for collecting current.

[0028] Optionally, the anode 101 and the cathode 401 are both hydrogen electrodes.

[0029] The anode chamber 104 and the cathode chamber 404 are connected by an external pipeline to form a loop for circulating hydrogen or hydrogen-containing gas.

[0030] Optionally, the anode-side cation exchange membrane 102 and the cathode-side cation exchange membrane 402 are both proton exchange membranes.

[0031] The proton exchange membrane is selected from at least one of a fluorosulfonic acid membrane, a fluorinated polymer sulfonic acid membrane, and a non-fluorinated polymer proton exchange membrane.

[0032] Optionally, the cation exchange membrane 201 is Na type;

[0033] The anion exchange membrane 202 is Cl type.

[0034] According to another aspect of the present application, a method for salt differential power generation using the above-mentioned salt differential power generation device is provided, comprising the following steps:

[0035] The high-salt solution is introduced into the brine chamber 301, and the low-salt solution is introduced into the fresh water chamber 302, and the salt concentration of the high-salt solution is higher than that of the low-salt solution; here, the concentration and dilution only refer to the high and low salt concentrations, for example, the fresh water chamber can be introduced into seawater, and the concentrated water chamber is introduced into brine (seawater desalination concentrate).

[0036] The electrolyte is circulated in the anode-side electrode liquid chamber 103, the cathode-side electrode liquid chamber 403, and the loop formed by the external pipeline;

[0037] The anode 101 undergoes an electrocatalytic oxidation reaction, and the cathode 401 undergoes an electrocatalytic reduction reaction.

[0038] Optionally, the acid electrolyte is circulated in the anode-side electrode liquid chamber 103 and the cathode-side electrode liquid chamber 403;

[0039] Optionally, the acid electrolyte is selected from at least one of H2SO4 and HClO4.

[0040] Optionally, a neutral supporting electrolyte can also be added to the acid electrolyte, and the neutral supporting electrolyte is at least one of NaCl, Na2SO4, NaNO3, KCl, K2SO4, and KNO3.

[0041] Hydrogen gas or hydrogen-rich gas is circulated in the anode chamber 104 and the cathode chamber 404 and the loop formed by the external pipeline;

[0042] The anode 101 undergoes an electrocatalytic oxidation reaction to consume hydrogen gas, and the cathode 401 undergoes an electrocatalytic reduction reaction to produce hydrogen gas. H2 is circulated through the pipeline without net consumption.

[0043] According to another aspect of the present application, a water-electricity cogeneration device is also provided, comprising a thermal seawater desalination module and a salt differential power generation module;

[0044] The salt differential power generation module is selected from the salt differential power generation device of any one of claims 1 to 6;

[0045] Seawater is introduced into the thermal seawater desalination module to discharge fresh water and brine, and the brine and seawater are introduced into the salt differential power generation device to generate electric energy and discharge diluted brine.

[0046] Optionally, the thermal desalination module is selected from one of a low-temperature multi-effect (MED) process device, a multi-stage flash (MSF) process device, and a vapor compression distillation process device.

[0047] The application can produce beneficial effects, including:

[0048] The salt difference power generation device and method provided by the application can efficiently utilize salt difference energy, is environmentally friendly and has no carbon emission; compared with using Fe 2+ / Fe 3+ or the oxidation-reduction reaction system of ferricyanide / ferrocyanide, the application is not limited by concentration polarization; compared with using a water electrolysis oxidation-reduction system, the overpotential is small and the efficiency is high; the amount of H2 is small, there is no danger, and there is no net consumption in the entire system. The water-electricity cogeneration device based on the salt difference power generation device of the application can fully utilize waste heat to produce fresh water while generating electricity, and has high efficiency and no pollution. BRIEF DESCRIPTION OF DRAWINGS

[0049] Figure 1 is a schematic diagram of the principle of salt difference power generation according to the application.

[0050] Figure 2 is a schematic diagram of the structure of the salt difference power generation module according to the application.

[0051] Figure 3 is a schematic diagram of the principle of the water-electricity cogeneration device according to the application.

[0052] Figure 3 is a schematic diagram of the principle of the water-electricity cogeneration device according to the application. DETAILED DESCRIPTION

[0053] The application will be described in detail below in conjunction with the examples, but the application is not limited to these examples.

[0054] Unless otherwise specified, the raw materials in the examples of the application are purchased through commercial channels.

[0055] Unless otherwise specified, the test methods all use conventional methods, and the instrument settings all use the recommended settings of the manufacturers.

[0056] According to one embodiment of the application, the salt difference power generation device comprises: an anode 101 and a cathode 401 arranged opposite to each other;

[0057] The anode 101 is provided with an anode-side cation exchange membrane 102 on the side close to the cathode 401, and an anode-side electrode liquid chamber 103 is provided on the side of the anode-side cation exchange membrane 102 away from the anode 101; the anode 101 is provided with an anode chamber 104 on the side away from the cathode 401;

[0058] The cathode 401 is provided with a cathode-side cation exchange membrane 402 on the side close to the anode 101, and a cathode-side electrode liquid chamber 403 is provided on the side of the cathode-side cation exchange membrane 402 away from the cathode 401; the cathode 401 is provided with a cathode chamber 404 on the side away from the anode 101;

[0059] The anode-side electrode liquid chamber 103 and the cathode-side electrode liquid chamber 403 are connected by external pipelines to form a loop for circulating electrolyte;

[0060] At least one brine chamber 301 and at least one fresh water chamber 302 are provided between the anode-side electrode liquid chamber 103 and the cathode-side electrode liquid chamber 403, and the brine chamber 301 and the fresh water chamber 302 are separated by a partition plate;

[0061] The partition plate is provided with a cation exchange membrane 201 or an anion exchange membrane 202;

[0062] The side of the brine chamber 301 close to the anode-side electrode liquid chamber 103 and the side of the fresh water chamber 302 away from the anode-side electrode liquid chamber 103 are provided with a cation exchange membrane 201;

[0063] The side of the brine chamber 301 close to the cathode-side electrode liquid chamber 403 and the side of the fresh water chamber 302 away from the cathode-side electrode liquid chamber 403 are provided with an anion exchange membrane 202.

[0064] The anode 101 and the cathode 401 are both gas diffusion electrodes;

[0065] The anode chamber 104 and the cathode chamber 404 are connected by external pipelines to form a loop for circulating hydrogen gas or hydrogen-rich gas.

[0066] The principle of salt differential power generation is shown in FIG. 1, high-salt solution is introduced into the brine chamber 301, and low-salt solution is introduced into the fresh water chamber 302, the salt concentration of the high-salt solution is higher than that of the low-salt solution; the anode-side electrode liquid chamber 103, the cathode-side electrode liquid chamber 403 and the loop formed by the external pipelines are circulated with electrolyte;

[0067] The anode-side electrode liquid chamber 103 and the cathode-side electrode liquid chamber 403 are circulated with acidic electrolyte;

[0068] The anode chamber 104 and the cathode chamber 404 and the loop formed by the external pipelines are circulated with hydrogen gas or hydrogen-rich gas;

[0069] The anode 101 consumes hydrogen gas by electrocatalytic oxidation reaction, and the cathode 401 produces hydrogen gas by electrocatalytic reduction reaction. H2 circulates through the pipelines between the anode and the cathode without net consumption.

[0070] When the high-salt solution and the low-salt solution flow in the respective chambers, the anions and cations in the high-salt solution migrate into the low-salt solution through the anion exchange membrane and the cation exchange membrane respectively under the driving of the concentration difference, thereby forming an internal current. The internal current can be converted into an external circuit current through the oxidation-reduction reaction of the cathode and the anode.

[0071] Example 1: Salinity power generation device

[0072] The salinity power generation device comprises an anode 101 and a cathode 401 arranged oppositely.

[0073] The anode 101 is provided with a cation exchange membrane 102 on the side close to the cathode 401, the cation exchange membrane 102 is provided with an anode-side electrode liquid chamber 103 on the side away from the anode 101, and the anode 101 is provided with an anode chamber 104 on the side away from the cathode 401.

[0074] The cathode 401 is provided with a cation exchange membrane 402 on the side close to the anode 101, the cation exchange membrane 402 is provided with a cathode-side electrode liquid chamber 403 on the side away from the cathode 401, and the cathode 401 is provided with a cathode chamber 404 on the side away from the anode 101.

[0075] The anode-side electrode liquid chamber 103 and the cathode-side electrode liquid chamber 403 are connected by external pipelines to form a loop for circulating electrolyte.

[0076] A plurality of brine chambers 301 and fresh water chambers 302 are arranged alternately between the anode-side electrode liquid chamber 103 and the cathode-side electrode liquid chamber 403, and the brine chambers 301 and the fresh water chambers 302 are separated by a partition plate.

[0077] The partition plate is provided with a cation exchange membrane 201 or an anion exchange membrane 202.

[0078] The brine chamber 301 is provided with the cation exchange membrane 201 on the side close to the anode-side electrode liquid chamber 103, and the fresh water chamber 302 is provided with the cation exchange membrane 201 on the side away from the anode-side electrode liquid chamber 103.

[0079] The brine chamber 301 is provided with the anion exchange membrane 202 on the side close to the cathode-side electrode liquid chamber 403, and the fresh water chamber 302 is provided with the anion exchange membrane 202 on the side away from the cathode-side electrode liquid chamber 403.

[0080] The anode chamber 104 and the cathode chamber 404 are connected by external pipelines to form a loop for circulating hydrogen or hydrogen-rich gas.

[0081] The anode 101 and the cathode 401 are both gas diffusion electrodes. The gas diffusion layer used is TGP-060. A mixture of 0.5 mg / cm 2 of carbon powder and PTFE (30% by mass) is coated on the gas diffusion layer, and then a catalyst slurry is scraped on the mixture. The slurry is composed of Pt / C (40% by mass, purchased from JM Company), Nafion solution (5% by mass, purchased from Dupon Company), and ethanol; the mass ratio of Nafion, Pt / C, and ethanol is 1:4:20. The anode 101 and the cathode 401 of the present embodiment are both prepared by using the above-mentioned process to prepare a gas diffusion electrode.

[0082] The prepared electrode is placed on one side of the anode-side cation exchange membrane 102 and the cathode-side cation exchange membrane 402 (both of which are Nafion-115 membranes), and is hot-pressed at 120°C and 2000 pounds of pressure for one minute to form an integrated membrane electrode. The size of the electrode used in the present embodiment is 10 cm x 10 cm. The anode and cathode membrane electrodes of the present embodiment are the same.

[0083] A stainless steel end plate with a point flow field, the prepared integrated membrane electrode, the cation exchange membrane Nafion-115, the cation exchange membrane 201 (FAB-PK-130), the anion exchange membrane 202 (FAA-3-PK-130), and a plastic separator are assembled into a battery, in which the anion exchange membrane and the cation exchange membrane are placed on one side of the separator, respectively. The number of repeating units of the anion and cation membranes in the present embodiment is 50.

[0084] Hydrogen is filled in the chambers (anode chamber and cathode chamber) formed between the stainless steel end plate and the membrane electrode, and the hydrogen chambers are connected by a gas guide pipe to circulate hydrogen in the battery.

[0085] 0.5 mol / L H2SO4 solution is filled in the anode electrode solution chamber 103 and the cathode electrode solution chamber 403, and 0.5 mol / L NaCl solution is used as the supporting electrolyte. The anode and cathode electrode solution chambers are connected by pipelines, and a peristaltic pump is arranged in the pipelines to circulate the solution.

[0086] 0.5 mol / L NaCl solution is filled in the brine chamber 301, and 0.01 mol / L NaCl solution is filled in the fresh water chamber 302. An Arbin programmable electronic load is used to test the i-V curve performance, and the highest power density is 1.2 W / m 2 .

[0087] Example 2 Water-electricity cogeneration device

[0088] A schematic diagram of the principle of the water-electricity cogeneration device is shown in FIG. 3, which comprises a thermal seawater desalination module and a salt differential power generation module, and the thermal seawater desalination module is communicated with the salt differential power generation module, wherein the salt differential power generation module adopts the structure of the salt differential power generation device of Example 1. The thermal seawater desalination module uses external heat energy (waste heat) to desalinate seawater to produce fresh water and brine, wherein the brine and seawater enter the salt differential power generation device to produce diluted brine, and the salt differential is used to generate electric energy for external transmission. The thermal seawater desalination module can be selected from any one of a low-temperature multi-effect (MED) process device, a multi-stage flash (MSF) process device, and a pressure vapor distillation process device.

[0089] The above is only a few embodiments of the present application, and does not limit the present application in any form. Although the preferred embodiments are disclosed above, the present application is not limited thereto. Any person skilled in the art can make some changes or modifications to the above disclosed technical contents without departing from the scope of the technical solutions of the present application, and such changes or modifications are equivalent to equivalent embodiments, which are all within the scope of the technical solutions.

Claims

1. A salinity power generation device characterized by comprising: The application relates to a hydrogen-oxygen fuel cell, which comprises: oppositely arranged anode 101 and cathode 401; the anode 101 is provided with an anode-side cation exchange membrane 102 on the side close to the cathode 401, the anode-side cation exchange membrane 102 is provided with an anode-side electrode liquid chamber 103 on the side away from the anode 101, and the anode 101 is provided with an anode chamber 104 on the side away from the cathode 401; the cathode 401 is provided with a cathode-side cation exchange membrane 402 on the side close to the anode 101, the cathode-side cation exchange membrane 402 is provided with a cathode-side electrode liquid chamber 403 on the side away from the cathode 401, and the cathode 401 is provided with a cathode chamber 404 on the side away from the anode 101; the anode-side electrode liquid chamber 103 and the cathode-side electrode liquid chamber 403 are connected by external pipelines to form a loop for circulating electrolyte; at least one brine chamber 301 and at least one fresh water chamber 302 are arranged between the anode-side electrode liquid chamber 103 and the cathode-side electrode liquid chamber 403, and the brine chamber 301 and the fresh water chamber 302 are separated by a partition plate; the partition plate is provided with a cation exchange membrane 201 or an anion exchange membrane 202; the brine chamber 301 is provided with the cation exchange membrane 201 on the side close to the anode-side electrode liquid chamber 103, and the fresh water chamber 302 is provided with the cation exchange membrane 201 on the side away from the anode-side electrode liquid chamber 103; the brine chamber 301 is provided with the anion exchange membrane 202 on the side close to the cathode-side electrode liquid chamber 403, and the fresh water chamber 302 is provided with the anion exchange membrane 202 on the side away from the cathode-side electrode liquid chamber 403.

2. The salinity power generation device according to claim 1, characterized by a plurality of alternately arranged brine chambers 301 and fresh water chambers 302 are arranged between the anode-side electrode liquid chamber 103 and the cathode-side electrode liquid chamber 403.

3. The salinity power generation device according to claim 1 or 2, characterized by the anode 101 and the cathode 401 are both gas diffusion electrodes; the gas diffusion electrode is composed of a support layer, a microporous layer and a catalytic layer which are stacked in sequence; the support layer is selected from at least one of carbon paper, carbon cloth, carbon felt, metal mesh and foamed metal; the microporous layer is formed by solidifying a mixture of carbon powder and a binder I; the binder I is selected from at least one of PTFE, PVDF, FEP and PFA; the catalytic layer is formed by solidifying a mixture of an electrocatalyst and a binder II; the binder II is selected from at least one of PTFE, PVDF, FEP, PFA and cation exchange resin; the active component of the electrocatalyst is selected from at least one of platinum, palladium, ruthenium, nickel, chromium, cobalt, copper, tungsten, iron, cerium, molybdenum and lead.

4. The salinity power generation device according to any one of claims 1 to 3, characterized by the anode 101 and the cathode 401 are both hydrogen electrodes; the anode chamber 104 and the cathode chamber 404 are connected by external pipelines to form a loop for circulating hydrogen or hydrogen-containing gas.

5. The salinity power generation device according to any one of claims 1 to 4, characterized by, the anode-side cation exchange membrane 102 and the cathode-side cation exchange membrane 402 are both proton exchange membranes; the proton exchange membrane is selected from at least one of fluorosulfonic acid membrane, fluorinated polymer sulfonic acid membrane and non-fluorinated polymer proton exchange membrane.

6. The salinity power generation device according to any one of claims 1 to 5, characterized by the cation exchange membrane 201 is Na type; the anion exchange membrane 202 is Cl type.

7. A method of salinity power generation using the salinity power generation device according to any one of claims 1 to 6, characterized by, the application further relates to a method for operating the hydrogen-oxygen fuel cell, which comprises the following steps: high-salt solution is introduced into the brine chamber 301, and low-salt solution is introduced into the fresh water chamber 302, and the salt concentration of the high-salt solution is higher than that of the low-salt solution. The anode-side electrode liquid chamber 103, the cathode-side electrode liquid chamber 403 and the circuit formed by the external pipeline communication thereof circulate electrolyte; The anode 101 generates electro-catalytic oxidation reaction, and the cathode 401 generates electro-catalytic reduction reaction. The anode-side electrode liquid chamber 103 and the cathode-side electrode liquid chamber 403 circulate acidic electrolyte; 8. The method of salinity power generation according to claim 7, wherein, The anode chamber 104 and the cathode chamber 404 and the circuit formed by the external pipeline communication thereof circulate hydrogen or hydrogen-rich gas; The anode 101 generates electro-catalytic oxidation reaction to consume hydrogen, and the cathode 401 generates electro-catalytic reduction reaction to produce hydrogen. The device comprises a thermal seawater desalination module and a salinity power generation module; 9. A water-electricity cogeneration device, characterized by, The salinity power generation module is selected from the salinity power generation device of any one of claims 1 to 6; Seawater is introduced into the thermal seawater desalination module to discharge fresh water and brine, and the brine and seawater are introduced into the salinity power generation device to generate electric energy and discharge diluted brine. The thermal seawater desalination module is selected from one of a low-temperature multi-effect process device, a multi-stage flash evaporation process device and a pressure vapor distillation desalination process device.

10. Use according to claim 9, characterized in that, ​

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